Improvement in micrometer-gages



A. BUNNAZ.

M-crometer Gages.

Patented August 19, 1873.

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ANTOINE BONNAZ, OF PARIS, FRANCE.

IMPROVEMENT IN MlCROMETER-GAGES.

Specication forming part of Letters Patent No. 141,915, dated August 19, 1873 application filed May 9, 1873.

To all whom it may concern:

Be it known that I, ANTOINE BoNNAz, of Paris, France, have invented a new and Improved Micrometer; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawing forming part of this specification. i

The invention relates to micrometer screwpresses for measuring articles in minute fractions, or with unusual accuracy, and will be first fully described and then clearly pointed out in the claims. p

Figure 1 is a side elevation partly broken away; Fig. 2, a vertical section through the axis of screw; Fig. 3, an'enlarged View of the abutment-screw and a section of the socket; Fig. 4, a plan View of the same; and Fig. 5, a plan View of the metallic spring-washer that tits between knob and socket.

In the drawing, A represents the frame that supports the screws; B C, the upper and lower screws; a-nd a a', the screw-sockets. The.

screws'are formed with threads, whose section shows an equilateral triangle, and which are reversed in their direction. E is a milled head or knob, swiveled on a screw, Gr, that is fastened in the head of screw C. D is a plain outer socket, rigidly attached to the screw G, while the knob E has a downward iiange, c, extending over the upper part d of socket. Between the part 0l` and knob E is a washer, M, having a series of springs, m m' m, which produce between the three parts C D E africtional connection that will cause them to turn together until a resistance is met with ade-- quate to overcome this friction. This spring is seen in detail in Fig. 5 of drawing. x .fr are packin g-rin gs letinto annular recesses of sockets D a to exclude dust. The socket D oi' the abutment-screw B is made as shown in Fig. 4, being cut diametrically and the two parts clamped together by a screw, V. A numerical circular notation is made upon the movable socket D, and a linear notation on the stationary socket a. f

The operation is asfollows: The abutmentscrew B being placed in position to receive the article to be measured, and the article being placed thereon, the knob E is turned with thengers,when the washer M, having springs Vm m m, will bind the socket D so as to compel the latter and the screw C to turn together until the end c reaches the top of the article. The knob will now continue to turn, while the screw C and socket D will stop, the two latter exhibiting a corresponding number in the vertical line marked o on the stationary scale. It' the article is too small to be reached by the top screw C the abutment B is raisedY to a greater or less extent.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is=

1. The washer M having the springs m m m and the swivel-screw G applied as a connection between the-parts C D and knob Ein the manner described, to cause them to rotate together until the article is reached, when the screw and socket may stop while the knob continues.

2. The combination, with vertically-notated stationary nut or socket a and a stationary support, B, of the screw C and knob E connected by friction, substantially as and for the purpose set forth.

ANTOINE BONNAZ.

Witnesses CHARLES DEsNos, EMILE DURAN. 

